/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.nulldev.util.io.serialization.objasm;

/**
 * A {@link ClassVisitor} that generates classes in bytecode form. More
 * precisely this visitor generates a byte array conforming to the Java class
 * file format. It can be used alone, to generate a Java class "from scratch",
 * or with one or more {@link ClassReader ClassReader} and adapter class visitor
 * to generate a modified class from one or more existing Java classes.
 * 
 * @author Eric Bruneton
 */
public class ClassWriter extends ClassVisitor {

	/**
	 * Flag to automatically compute the maximum stack size and the maximum number
	 * of local variables of methods. If this flag is set, then the arguments of the
	 * {@link MethodVisitor#visitMaxs visitMaxs} method of the {@link MethodVisitor}
	 * returned by the {@link #visitMethod visitMethod} method will be ignored, and
	 * computed automatically from the signature and the bytecode of each method.
	 * 
	 * @see #ClassWriter(int)
	 */
	public static final int COMPUTE_MAXS = 1;

	/**
	 * Flag to automatically compute the stack map frames of methods from scratch.
	 * If this flag is set, then the calls to the {@link MethodVisitor#visitFrame}
	 * method are ignored, and the stack map frames are recomputed from the methods
	 * bytecode. The arguments of the {@link MethodVisitor#visitMaxs visitMaxs}
	 * method are also ignored and recomputed from the bytecode. In other words,
	 * computeFrames implies computeMaxs.
	 * 
	 * @see #ClassWriter(int)
	 */
	public static final int COMPUTE_FRAMES = 2;

	/**
	 * Pseudo access flag to distinguish between the synthetic attribute and the
	 * synthetic access flag.
	 */
	static final int ACC_SYNTHETIC_ATTRIBUTE = 0x40000;

	/**
	 * Factor to convert from ACC_SYNTHETIC_ATTRIBUTE to Opcode.ACC_SYNTHETIC.
	 */
	static final int TO_ACC_SYNTHETIC = ACC_SYNTHETIC_ATTRIBUTE / Opcodes.ACC_SYNTHETIC;

	/**
	 * The type of instructions without any argument.
	 */
	static final int NOARG_INSN = 0;

	/**
	 * The type of instructions with an signed byte argument.
	 */
	static final int SBYTE_INSN = 1;

	/**
	 * The type of instructions with an signed short argument.
	 */
	static final int SHORT_INSN = 2;

	/**
	 * The type of instructions with a local variable index argument.
	 */
	static final int VAR_INSN = 3;

	/**
	 * The type of instructions with an implicit local variable index argument.
	 */
	static final int IMPLVAR_INSN = 4;

	/**
	 * The type of instructions with a type descriptor argument.
	 */
	static final int TYPE_INSN = 5;

	/**
	 * The type of field and method invocations instructions.
	 */
	static final int FIELDORMETH_INSN = 6;

	/**
	 * The type of the INVOKEINTERFACE/INVOKEDYNAMIC instruction.
	 */
	static final int ITFMETH_INSN = 7;

	/**
	 * The type of the INVOKEDYNAMIC instruction.
	 */
	static final int INDYMETH_INSN = 8;

	/**
	 * The type of instructions with a 2 bytes bytecode offset label.
	 */
	static final int LABEL_INSN = 9;

	/**
	 * The type of instructions with a 4 bytes bytecode offset label.
	 */
	static final int LABELW_INSN = 10;

	/**
	 * The type of the LDC instruction.
	 */
	static final int LDC_INSN = 11;

	/**
	 * The type of the LDC_W and LDC2_W instructions.
	 */
	static final int LDCW_INSN = 12;

	/**
	 * The type of the IINC instruction.
	 */
	static final int IINC_INSN = 13;

	/**
	 * The type of the TABLESWITCH instruction.
	 */
	static final int TABL_INSN = 14;

	/**
	 * The type of the LOOKUPSWITCH instruction.
	 */
	static final int LOOK_INSN = 15;

	/**
	 * The type of the MULTIANEWARRAY instruction.
	 */
	static final int MANA_INSN = 16;

	/**
	 * The type of the WIDE instruction.
	 */
	static final int WIDE_INSN = 17;

	/**
	 * The instruction types of all JVM opcodes.
	 */
	static final byte[] TYPE;

	/**
	 * The type of CONSTANT_Class constant pool items.
	 */
	static final int CLASS = 7;

	/**
	 * The type of CONSTANT_Fieldref constant pool items.
	 */
	static final int FIELD = 9;

	/**
	 * The type of CONSTANT_Methodref constant pool items.
	 */
	static final int METH = 10;

	/**
	 * The type of CONSTANT_InterfaceMethodref constant pool items.
	 */
	static final int IMETH = 11;

	/**
	 * The type of CONSTANT_String constant pool items.
	 */
	static final int STR = 8;

	/**
	 * The type of CONSTANT_Integer constant pool items.
	 */
	static final int INT = 3;

	/**
	 * The type of CONSTANT_Float constant pool items.
	 */
	static final int FLOAT = 4;

	/**
	 * The type of CONSTANT_Long constant pool items.
	 */
	static final int LONG = 5;

	/**
	 * The type of CONSTANT_Double constant pool items.
	 */
	static final int DOUBLE = 6;

	/**
	 * The type of CONSTANT_NameAndType constant pool items.
	 */
	static final int NAME_TYPE = 12;

	/**
	 * The type of CONSTANT_Utf8 constant pool items.
	 */
	static final int UTF8 = 1;

	/**
	 * The type of CONSTANT_MethodType constant pool items.
	 */
	static final int MTYPE = 16;

	/**
	 * The type of CONSTANT_MethodHandle constant pool items.
	 */
	static final int HANDLE = 15;

	/**
	 * The type of CONSTANT_InvokeDynamic constant pool items.
	 */
	static final int INDY = 18;

	/**
	 * The base value for all CONSTANT_MethodHandle constant pool items. Internally,
	 * ASM store the 9 variations of CONSTANT_MethodHandle into 9 different items.
	 */
	static final int HANDLE_BASE = 20;

	/**
	 * Normal type Item stored in the ClassWriter {@link ClassWriter#typeTable},
	 * instead of the constant pool, in order to avoid clashes with normal constant
	 * pool items in the ClassWriter constant pool's hash table.
	 */
	static final int TYPE_NORMAL = 30;

	/**
	 * Uninitialized type Item stored in the ClassWriter
	 * {@link ClassWriter#typeTable}, instead of the constant pool, in order to
	 * avoid clashes with normal constant pool items in the ClassWriter constant
	 * pool's hash table.
	 */
	static final int TYPE_UNINIT = 31;

	/**
	 * Merged type Item stored in the ClassWriter {@link ClassWriter#typeTable},
	 * instead of the constant pool, in order to avoid clashes with normal constant
	 * pool items in the ClassWriter constant pool's hash table.
	 */
	static final int TYPE_MERGED = 32;

	/**
	 * The type of BootstrapMethods items. These items are stored in a special class
	 * attribute named BootstrapMethods and not in the constant pool.
	 */
	static final int BSM = 33;

	/**
	 * The class reader from which this class writer was constructed, if any.
	 */
	ClassReader cr;

	/**
	 * Minor and major version numbers of the class to be generated.
	 */
	int version;

	/**
	 * Index of the next item to be added in the constant pool.
	 */
	int index;

	/**
	 * The constant pool of this class.
	 */
	final ByteVector pool;

	/**
	 * The constant pool's hash table data.
	 */
	Item[] items;

	/**
	 * The threshold of the constant pool's hash table.
	 */
	int threshold;

	/**
	 * A reusable key used to look for items in the {@link #items} hash table.
	 */
	final Item key;

	/**
	 * A reusable key used to look for items in the {@link #items} hash table.
	 */
	final Item key2;

	/**
	 * A reusable key used to look for items in the {@link #items} hash table.
	 */
	final Item key3;

	/**
	 * A reusable key used to look for items in the {@link #items} hash table.
	 */
	final Item key4;

	/**
	 * A type table used to temporarily store internal names that will not
	 * necessarily be stored in the constant pool. This type table is used by the
	 * control flow and data flow analysis algorithm used to compute stack map
	 * frames from scratch. This array associates to each index <tt>i</tt> the Item
	 * whose index is <tt>i</tt>. All Item objects stored in this array are also
	 * stored in the {@link #items} hash table. These two arrays allow to retrieve
	 * an Item from its index or, conversely, to get the index of an Item from its
	 * value. Each Item stores an internal name in its {@link Item#strVal1} field.
	 */
	Item[] typeTable;

	/**
	 * Number of elements in the {@link #typeTable} array.
	 */
	private short typeCount;

	/**
	 * The access flags of this class.
	 */
	private int access;

	/**
	 * The constant pool item that contains the internal name of this class.
	 */
	private int name;

	/**
	 * The internal name of this class.
	 */
	String thisName;

	/**
	 * The constant pool item that contains the signature of this class.
	 */
	private int signature;

	/**
	 * The constant pool item that contains the internal name of the super class of
	 * this class.
	 */
	private int superName;

	/**
	 * Number of interfaces implemented or extended by this class or interface.
	 */
	private int interfaceCount;

	/**
	 * The interfaces implemented or extended by this class or interface. More
	 * precisely, this array contains the indexes of the constant pool items that
	 * contain the internal names of these interfaces.
	 */
	private int[] interfaces;

	/**
	 * The index of the constant pool item that contains the name of the source file
	 * from which this class was compiled.
	 */
	private int sourceFile;

	/**
	 * The SourceDebug attribute of this class.
	 */
	private ByteVector sourceDebug;

	/**
	 * The constant pool item that contains the name of the enclosing class of this
	 * class.
	 */
	private int enclosingMethodOwner;

	/**
	 * The constant pool item that contains the name and descriptor of the enclosing
	 * method of this class.
	 */
	private int enclosingMethod;

	/**
	 * The runtime visible annotations of this class.
	 */
	private AnnotationWriter anns;

	/**
	 * The runtime invisible annotations of this class.
	 */
	private AnnotationWriter ianns;

	/**
	 * The runtime visible type annotations of this class.
	 */
	private AnnotationWriter tanns;

	/**
	 * The runtime invisible type annotations of this class.
	 */
	private AnnotationWriter itanns;

	/**
	 * The non standard attributes of this class.
	 */
	private Attribute attrs;

	/**
	 * The number of entries in the InnerClasses attribute.
	 */
	private int innerClassesCount;

	/**
	 * The InnerClasses attribute.
	 */
	private ByteVector innerClasses;

	/**
	 * The number of entries in the BootstrapMethods attribute.
	 */
	int bootstrapMethodsCount;

	/**
	 * The BootstrapMethods attribute.
	 */
	ByteVector bootstrapMethods;

	/**
	 * The fields of this class. These fields are stored in a linked list of
	 * {@link FieldWriter} objects, linked to each other by their
	 * {@link FieldWriter#fv} field. This field stores the first element of this
	 * list.
	 */
	FieldWriter firstField;

	/**
	 * The fields of this class. These fields are stored in a linked list of
	 * {@link FieldWriter} objects, linked to each other by their
	 * {@link FieldWriter#fv} field. This field stores the last element of this
	 * list.
	 */
	FieldWriter lastField;

	/**
	 * The methods of this class. These methods are stored in a linked list of
	 * {@link MethodWriter} objects, linked to each other by their
	 * {@link MethodWriter#mv} field. This field stores the first element of this
	 * list.
	 */
	MethodWriter firstMethod;

	/**
	 * The methods of this class. These methods are stored in a linked list of
	 * {@link MethodWriter} objects, linked to each other by their
	 * {@link MethodWriter#mv} field. This field stores the last element of this
	 * list.
	 */
	MethodWriter lastMethod;

	/**
	 * <tt>true</tt> if the maximum stack size and number of local variables must be
	 * automatically computed.
	 */
	private final boolean computeMaxs;

	/**
	 * <tt>true</tt> if the stack map frames must be recomputed from scratch.
	 */
	private final boolean computeFrames;

	/**
	 * <tt>true</tt> if the stack map tables of this class are invalid. The
	 * {@link MethodWriter#resizeInstructions} method cannot transform existing
	 * stack map tables, and so produces potentially invalid classes when it is
	 * executed. In this case the class is reread and rewritten with the
	 * {@link #COMPUTE_FRAMES} option (the resizeInstructions method can resize
	 * stack map tables when this option is used).
	 */
	boolean invalidFrames;

	// ------------------------------------------------------------------------
	// Static initializer
	// ------------------------------------------------------------------------

	/**
	 * Computes the instruction types of JVM opcodes.
	 */
	static {
		int i;
		byte[] b = new byte[220];
		String s = "AAAAAAAAAAAAAAAABCLMMDDDDDEEEEEEEEEEEEEEEEEEEEAAAAAAAADD" + "DDDEEEEEEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
				+ "AAAAAAAAAAAAAAAAANAAAAAAAAAAAAAAAAAAAAJJJJJJJJJJJJJJJJDOPAA" + "AAAAGGGGGGGHIFBFAAFFAARQJJKKJJJJJJJJJJJJJJJJJJ";
		for (i = 0; i < b.length; ++i) {
			b[i] = (byte) (s.charAt(i) - 'A');
		}
		TYPE = b;

		// code to generate the above string
		//
		// // SBYTE_INSN instructions
		// b[Constants.NEWARRAY] = SBYTE_INSN;
		// b[Constants.BIPUSH] = SBYTE_INSN;
		//
		// // SHORT_INSN instructions
		// b[Constants.SIPUSH] = SHORT_INSN;
		//
		// // (IMPL)VAR_INSN instructions
		// b[Constants.RET] = VAR_INSN;
		// for (i = Constants.ILOAD; i <= Constants.ALOAD; ++i) {
		// b[i] = VAR_INSN;
		// }
		// for (i = Constants.ISTORE; i <= Constants.ASTORE; ++i) {
		// b[i] = VAR_INSN;
		// }
		// for (i = 26; i <= 45; ++i) { // ILOAD_0 to ALOAD_3
		// b[i] = IMPLVAR_INSN;
		// }
		// for (i = 59; i <= 78; ++i) { // ISTORE_0 to ASTORE_3
		// b[i] = IMPLVAR_INSN;
		// }
		//
		// // TYPE_INSN instructions
		// b[Constants.NEW] = TYPE_INSN;
		// b[Constants.ANEWARRAY] = TYPE_INSN;
		// b[Constants.CHECKCAST] = TYPE_INSN;
		// b[Constants.INSTANCEOF] = TYPE_INSN;
		//
		// // (Set)FIELDORMETH_INSN instructions
		// for (i = Constants.GETSTATIC; i <= Constants.INVOKESTATIC; ++i) {
		// b[i] = FIELDORMETH_INSN;
		// }
		// b[Constants.INVOKEINTERFACE] = ITFMETH_INSN;
		// b[Constants.INVOKEDYNAMIC] = INDYMETH_INSN;
		//
		// // LABEL(W)_INSN instructions
		// for (i = Constants.IFEQ; i <= Constants.JSR; ++i) {
		// b[i] = LABEL_INSN;
		// }
		// b[Constants.IFNULL] = LABEL_INSN;
		// b[Constants.IFNONNULL] = LABEL_INSN;
		// b[200] = LABELW_INSN; // GOTO_W
		// b[201] = LABELW_INSN; // JSR_W
		// // temporary opcodes used internally by ASM - see Label and
		// MethodWriter
		// for (i = 202; i < 220; ++i) {
		// b[i] = LABEL_INSN;
		// }
		//
		// // LDC(_W) instructions
		// b[Constants.LDC] = LDC_INSN;
		// b[19] = LDCW_INSN; // LDC_W
		// b[20] = LDCW_INSN; // LDC2_W
		//
		// // special instructions
		// b[Constants.IINC] = IINC_INSN;
		// b[Constants.TABLESWITCH] = TABL_INSN;
		// b[Constants.LOOKUPSWITCH] = LOOK_INSN;
		// b[Constants.MULTIANEWARRAY] = MANA_INSN;
		// b[196] = WIDE_INSN; // WIDE
		//
		// for (i = 0; i < b.length; ++i) {
		// System.err.print((char)('A' + b[i]));
		// }
		// System.err.println();
	}

	// ------------------------------------------------------------------------
	// Constructor
	// ------------------------------------------------------------------------

	/**
	 * Constructs a new {@link ClassWriter} object.
	 * 
	 * @param flags option flags that can be used to modify the default behavior of
	 *              this class. See {@link #COMPUTE_MAXS}, {@link #COMPUTE_FRAMES}.
	 */
	public ClassWriter(final int flags) {
		super(Opcodes.ASM5);
		index = 1;
		pool = new ByteVector();
		items = new Item[256];
		threshold = (int) (0.75d * items.length);
		key = new Item();
		key2 = new Item();
		key3 = new Item();
		key4 = new Item();
		this.computeMaxs = (flags & COMPUTE_MAXS) != 0;
		this.computeFrames = (flags & COMPUTE_FRAMES) != 0;
	}

	/**
	 * Constructs a new {@link ClassWriter} object and enables optimizations for
	 * "mostly add" bytecode transformations. These optimizations are the following:
	 * 
	 * <ul>
	 * <li>The constant pool from the original class is copied as is in the new
	 * class, which saves time. New constant pool entries will be added at the end
	 * if necessary, but unused constant pool entries <i>won't be removed</i>.</li>
	 * <li>Methods that are not transformed are copied as is in the new class,
	 * directly from the original class bytecode (i.e. without emitting visit events
	 * for all the method instructions), which saves a <i>lot</i> of time.
	 * Untransformed methods are detected by the fact that the {@link ClassReader}
	 * receives {@link MethodVisitor} objects that come from a {@link ClassWriter}
	 * (and not from any other {@link ClassVisitor} instance).</li>
	 * </ul>
	 * 
	 * @param classReader the {@link ClassReader} used to read the original class.
	 *                    It will be used to copy the entire constant pool from the
	 *                    original class and also to copy other fragments of
	 *                    original bytecode where applicable.
	 * @param flags       option flags that can be used to modify the default
	 *                    behavior of this class. <i>These option flags do not
	 *                    affect methods that are copied as is in the new class.
	 *                    This means that the maximum stack size nor the stack
	 *                    frames will be computed for these methods</i>. See
	 *                    {@link #COMPUTE_MAXS}, {@link #COMPUTE_FRAMES}.
	 */
	public ClassWriter(final ClassReader classReader, final int flags) {
		this(flags);
		classReader.copyPool(this);
		this.cr = classReader;
	}

	// ------------------------------------------------------------------------
	// Implementation of the ClassVisitor abstract class
	// ------------------------------------------------------------------------

	@Override
	public final void visit(final int version, final int access, final String name, final String signature, final String superName, final String[] interfaces) {
		this.version = version;
		this.access = access;
		this.name = newClass(name);
		thisName = name;
		if (ClassReader.SIGNATURES && signature != null) {
			this.signature = newUTF8(signature);
		}
		this.superName = superName == null ? 0 : newClass(superName);
		if (interfaces != null && interfaces.length > 0) {
			interfaceCount = interfaces.length;
			this.interfaces = new int[interfaceCount];
			for (int i = 0; i < interfaceCount; ++i) {
				this.interfaces[i] = newClass(interfaces[i]);
			}
		}
	}

	@Override
	public final void visitSource(final String file, final String debug) {
		if (file != null) {
			sourceFile = newUTF8(file);
		}
		if (debug != null) {
			sourceDebug = new ByteVector().putUTF8(debug);
		}
	}

	@Override
	public final void visitOuterClass(final String owner, final String name, final String desc) {
		enclosingMethodOwner = newClass(owner);
		if (name != null && desc != null) {
			enclosingMethod = newNameType(name, desc);
		}
	}

	@Override
	public final AnnotationVisitor visitAnnotation(final String desc, final boolean visible) {
		if (!ClassReader.ANNOTATIONS) {
			return null;
		}
		ByteVector bv = new ByteVector();
		// write type, and reserve space for values count
		bv.putShort(newUTF8(desc)).putShort(0);
		AnnotationWriter aw = new AnnotationWriter(this, true, bv, bv, 2);
		if (visible) {
			aw.next = anns;
			anns = aw;
		} else {
			aw.next = ianns;
			ianns = aw;
		}
		return aw;
	}

	@Override
	public final AnnotationVisitor visitTypeAnnotation(int typeRef, TypePath typePath, final String desc, final boolean visible) {
		if (!ClassReader.ANNOTATIONS) {
			return null;
		}
		ByteVector bv = new ByteVector();
		// write target_type and target_info
		AnnotationWriter.putTarget(typeRef, typePath, bv);
		// write type, and reserve space for values count
		bv.putShort(newUTF8(desc)).putShort(0);
		AnnotationWriter aw = new AnnotationWriter(this, true, bv, bv, bv.length - 2);
		if (visible) {
			aw.next = tanns;
			tanns = aw;
		} else {
			aw.next = itanns;
			itanns = aw;
		}
		return aw;
	}

	@Override
	public final void visitAttribute(final Attribute attr) {
		attr.next = attrs;
		attrs = attr;
	}

	@Override
	public final void visitInnerClass(final String name, final String outerName, final String innerName, final int access) {
		if (innerClasses == null) {
			innerClasses = new ByteVector();
		}
		++innerClassesCount;
		innerClasses.putShort(name == null ? 0 : newClass(name));
		innerClasses.putShort(outerName == null ? 0 : newClass(outerName));
		innerClasses.putShort(innerName == null ? 0 : newUTF8(innerName));
		innerClasses.putShort(access);
	}

	@Override
	public final FieldVisitor visitField(final int access, final String name, final String desc, final String signature, final Object value) {
		return new FieldWriter(this, access, name, desc, signature, value);
	}

	@Override
	public final MethodVisitor visitMethod(final int access, final String name, final String desc, final String signature, final String[] exceptions) {
		return new MethodWriter(this, access, name, desc, signature, exceptions, computeMaxs, computeFrames);
	}

	@Override
	public final void visitEnd() {
	}

	// ------------------------------------------------------------------------
	// Other public methods
	// ------------------------------------------------------------------------

	/**
	 * Returns the bytecode of the class that was build with this class writer.
	 * 
	 * @return the bytecode of the class that was build with this class writer.
	 */
	public byte[] toByteArray() {
		if (index > 0xFFFF) {
			throw new RuntimeException("Class file too large!");
		}
		// computes the real size of the bytecode of this class
		int size = 24 + 2 * interfaceCount;
		int nbFields = 0;
		FieldWriter fb = firstField;
		while (fb != null) {
			++nbFields;
			size += fb.getSize();
			fb = (FieldWriter) fb.fv;
		}
		int nbMethods = 0;
		MethodWriter mb = firstMethod;
		while (mb != null) {
			++nbMethods;
			size += mb.getSize();
			mb = (MethodWriter) mb.mv;
		}
		int attributeCount = 0;
		if (bootstrapMethods != null) {
			// we put it as first attribute in order to improve a bit
			// ClassReader.copyBootstrapMethods
			++attributeCount;
			size += 8 + bootstrapMethods.length;
			newUTF8("BootstrapMethods");
		}
		if (ClassReader.SIGNATURES && signature != 0) {
			++attributeCount;
			size += 8;
			newUTF8("Signature");
		}
		if (sourceFile != 0) {
			++attributeCount;
			size += 8;
			newUTF8("SourceFile");
		}
		if (sourceDebug != null) {
			++attributeCount;
			size += sourceDebug.length + 4;
			newUTF8("SourceDebugExtension");
		}
		if (enclosingMethodOwner != 0) {
			++attributeCount;
			size += 10;
			newUTF8("EnclosingMethod");
		}
		if ((access & Opcodes.ACC_DEPRECATED) != 0) {
			++attributeCount;
			size += 6;
			newUTF8("Deprecated");
		}
		if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
			if ((version & 0xFFFF) < Opcodes.V1_5 || (access & ACC_SYNTHETIC_ATTRIBUTE) != 0) {
				++attributeCount;
				size += 6;
				newUTF8("Synthetic");
			}
		}
		if (innerClasses != null) {
			++attributeCount;
			size += 8 + innerClasses.length;
			newUTF8("InnerClasses");
		}
		if (ClassReader.ANNOTATIONS && anns != null) {
			++attributeCount;
			size += 8 + anns.getSize();
			newUTF8("RuntimeVisibleAnnotations");
		}
		if (ClassReader.ANNOTATIONS && ianns != null) {
			++attributeCount;
			size += 8 + ianns.getSize();
			newUTF8("RuntimeInvisibleAnnotations");
		}
		if (ClassReader.ANNOTATIONS && tanns != null) {
			++attributeCount;
			size += 8 + tanns.getSize();
			newUTF8("RuntimeVisibleTypeAnnotations");
		}
		if (ClassReader.ANNOTATIONS && itanns != null) {
			++attributeCount;
			size += 8 + itanns.getSize();
			newUTF8("RuntimeInvisibleTypeAnnotations");
		}
		if (attrs != null) {
			attributeCount += attrs.getCount();
			size += attrs.getSize(this, null, 0, -1, -1);
		}
		size += pool.length;
		// allocates a byte vector of this size, in order to avoid unnecessary
		// arraycopy operations in the ByteVector.enlarge() method
		ByteVector out = new ByteVector(size);
		out.putInt(0xCAFEBABE).putInt(version);
		out.putShort(index).putByteArray(pool.data, 0, pool.length);
		int mask = Opcodes.ACC_DEPRECATED | ACC_SYNTHETIC_ATTRIBUTE | ((access & ACC_SYNTHETIC_ATTRIBUTE) / TO_ACC_SYNTHETIC);
		out.putShort(access & ~mask).putShort(name).putShort(superName);
		out.putShort(interfaceCount);
		for (int i = 0; i < interfaceCount; ++i) {
			out.putShort(interfaces[i]);
		}
		out.putShort(nbFields);
		fb = firstField;
		while (fb != null) {
			fb.put(out);
			fb = (FieldWriter) fb.fv;
		}
		out.putShort(nbMethods);
		mb = firstMethod;
		while (mb != null) {
			mb.put(out);
			mb = (MethodWriter) mb.mv;
		}
		out.putShort(attributeCount);
		if (bootstrapMethods != null) {
			out.putShort(newUTF8("BootstrapMethods"));
			out.putInt(bootstrapMethods.length + 2).putShort(bootstrapMethodsCount);
			out.putByteArray(bootstrapMethods.data, 0, bootstrapMethods.length);
		}
		if (ClassReader.SIGNATURES && signature != 0) {
			out.putShort(newUTF8("Signature")).putInt(2).putShort(signature);
		}
		if (sourceFile != 0) {
			out.putShort(newUTF8("SourceFile")).putInt(2).putShort(sourceFile);
		}
		if (sourceDebug != null) {
			int len = sourceDebug.length - 2;
			out.putShort(newUTF8("SourceDebugExtension")).putInt(len);
			out.putByteArray(sourceDebug.data, 2, len);
		}
		if (enclosingMethodOwner != 0) {
			out.putShort(newUTF8("EnclosingMethod")).putInt(4);
			out.putShort(enclosingMethodOwner).putShort(enclosingMethod);
		}
		if ((access & Opcodes.ACC_DEPRECATED) != 0) {
			out.putShort(newUTF8("Deprecated")).putInt(0);
		}
		if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
			if ((version & 0xFFFF) < Opcodes.V1_5 || (access & ACC_SYNTHETIC_ATTRIBUTE) != 0) {
				out.putShort(newUTF8("Synthetic")).putInt(0);
			}
		}
		if (innerClasses != null) {
			out.putShort(newUTF8("InnerClasses"));
			out.putInt(innerClasses.length + 2).putShort(innerClassesCount);
			out.putByteArray(innerClasses.data, 0, innerClasses.length);
		}
		if (ClassReader.ANNOTATIONS && anns != null) {
			out.putShort(newUTF8("RuntimeVisibleAnnotations"));
			anns.put(out);
		}
		if (ClassReader.ANNOTATIONS && ianns != null) {
			out.putShort(newUTF8("RuntimeInvisibleAnnotations"));
			ianns.put(out);
		}
		if (ClassReader.ANNOTATIONS && tanns != null) {
			out.putShort(newUTF8("RuntimeVisibleTypeAnnotations"));
			tanns.put(out);
		}
		if (ClassReader.ANNOTATIONS && itanns != null) {
			out.putShort(newUTF8("RuntimeInvisibleTypeAnnotations"));
			itanns.put(out);
		}
		if (attrs != null) {
			attrs.put(this, null, 0, -1, -1, out);
		}
		if (invalidFrames) {
			ClassWriter cw = new ClassWriter(COMPUTE_FRAMES);
			new ClassReader(out.data).accept(cw, ClassReader.SKIP_FRAMES);
			return cw.toByteArray();
		}
		return out.data;
	}

	// ------------------------------------------------------------------------
	// Utility methods: constant pool management
	// ------------------------------------------------------------------------

	/**
	 * Adds a number or string constant to the constant pool of the class being
	 * build. Does nothing if the constant pool already contains a similar item.
	 * 
	 * @param cst the value of the constant to be added to the constant pool. This
	 *            parameter must be an {@link Integer}, a {@link Float}, a
	 *            {@link Long}, a {@link Double}, a {@link String} or a
	 *            {@link Type}.
	 * @return a new or already existing constant item with the given value.
	 */
	Item newConstItem(final Object cst) {
		if (cst instanceof Integer) {
			int val = ((Integer) cst).intValue();
			return newInteger(val);
		} else if (cst instanceof Byte) {
			int val = ((Byte) cst).intValue();
			return newInteger(val);
		} else if (cst instanceof Character) {
			int val = ((Character) cst).charValue();
			return newInteger(val);
		} else if (cst instanceof Short) {
			int val = ((Short) cst).intValue();
			return newInteger(val);
		} else if (cst instanceof Boolean) {
			int val = ((Boolean) cst).booleanValue() ? 1 : 0;
			return newInteger(val);
		} else if (cst instanceof Float) {
			float val = ((Float) cst).floatValue();
			return newFloat(val);
		} else if (cst instanceof Long) {
			long val = ((Long) cst).longValue();
			return newLong(val);
		} else if (cst instanceof Double) {
			double val = ((Double) cst).doubleValue();
			return newDouble(val);
		} else if (cst instanceof String) {
			return newString((String) cst);
		} else if (cst instanceof Type) {
			Type t = (Type) cst;
			int s = t.getSort();
			if (s == Type.OBJECT) {
				return newClassItem(t.getInternalName());
			} else if (s == Type.METHOD) {
				return newMethodTypeItem(t.getDescriptor());
			} else { // s == primitive type or array
				return newClassItem(t.getDescriptor());
			}
		} else if (cst instanceof Handle) {
			Handle h = (Handle) cst;
			return newHandleItem(h.tag, h.owner, h.name, h.desc);
		} else {
			throw new IllegalArgumentException("value " + cst);
		}
	}

	/**
	 * Adds a number or string constant to the constant pool of the class being
	 * build. Does nothing if the constant pool already contains a similar item.
	 * <i>This method is intended for {@link Attribute} sub classes, and is normally
	 * not needed by class generators or adapters.</i>
	 * 
	 * @param cst the value of the constant to be added to the constant pool. This
	 *            parameter must be an {@link Integer}, a {@link Float}, a
	 *            {@link Long}, a {@link Double} or a {@link String}.
	 * @return the index of a new or already existing constant item with the given
	 *         value.
	 */
	public int newConst(final Object cst) {
		return newConstItem(cst).index;
	}

	/**
	 * Adds an UTF8 string to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item. <i>This method
	 * is intended for {@link Attribute} sub classes, and is normally not needed by
	 * class generators or adapters.</i>
	 * 
	 * @param value the String value.
	 * @return the index of a new or already existing UTF8 item.
	 */
	public int newUTF8(final String value) {
		key.set(UTF8, value, null, null);
		Item result = get(key);
		if (result == null) {
			pool.putByte(UTF8).putUTF8(value);
			result = new Item(index++, key);
			put(result);
		}
		return result.index;
	}

	/**
	 * Adds a class reference to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item. <i>This method
	 * is intended for {@link Attribute} sub classes, and is normally not needed by
	 * class generators or adapters.</i>
	 * 
	 * @param value the internal name of the class.
	 * @return a new or already existing class reference item.
	 */
	Item newClassItem(final String value) {
		key2.set(CLASS, value, null, null);
		Item result = get(key2);
		if (result == null) {
			pool.put12(CLASS, newUTF8(value));
			result = new Item(index++, key2);
			put(result);
		}
		return result;
	}

	/**
	 * Adds a class reference to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item. <i>This method
	 * is intended for {@link Attribute} sub classes, and is normally not needed by
	 * class generators or adapters.</i>
	 * 
	 * @param value the internal name of the class.
	 * @return the index of a new or already existing class reference item.
	 */
	public int newClass(final String value) {
		return newClassItem(value).index;
	}

	/**
	 * Adds a method type reference to the constant pool of the class being build.
	 * Does nothing if the constant pool already contains a similar item. <i>This
	 * method is intended for {@link Attribute} sub classes, and is normally not
	 * needed by class generators or adapters.</i>
	 * 
	 * @param methodDesc method descriptor of the method type.
	 * @return a new or already existing method type reference item.
	 */
	Item newMethodTypeItem(final String methodDesc) {
		key2.set(MTYPE, methodDesc, null, null);
		Item result = get(key2);
		if (result == null) {
			pool.put12(MTYPE, newUTF8(methodDesc));
			result = new Item(index++, key2);
			put(result);
		}
		return result;
	}

	/**
	 * Adds a method type reference to the constant pool of the class being build.
	 * Does nothing if the constant pool already contains a similar item. <i>This
	 * method is intended for {@link Attribute} sub classes, and is normally not
	 * needed by class generators or adapters.</i>
	 * 
	 * @param methodDesc method descriptor of the method type.
	 * @return the index of a new or already existing method type reference item.
	 */
	public int newMethodType(final String methodDesc) {
		return newMethodTypeItem(methodDesc).index;
	}

	/**
	 * Adds a handle to the constant pool of the class being build. Does nothing if
	 * the constant pool already contains a similar item. <i>This method is intended
	 * for {@link Attribute} sub classes, and is normally not needed by class
	 * generators or adapters.</i>
	 * 
	 * @param tag   the kind of this handle. Must be {@link Opcodes#H_GETFIELD},
	 *              {@link Opcodes#H_GETSTATIC}, {@link Opcodes#H_PUTFIELD},
	 *              {@link Opcodes#H_PUTSTATIC}, {@link Opcodes#H_INVOKEVIRTUAL},
	 *              {@link Opcodes#H_INVOKESTATIC}, {@link Opcodes#H_INVOKESPECIAL},
	 *              {@link Opcodes#H_NEWINVOKESPECIAL} or
	 *              {@link Opcodes#H_INVOKEINTERFACE}.
	 * @param owner the internal name of the field or method owner class.
	 * @param name  the name of the field or method.
	 * @param desc  the descriptor of the field or method.
	 * @return a new or an already existing method type reference item.
	 */
	Item newHandleItem(final int tag, final String owner, final String name, final String desc) {
		key4.set(HANDLE_BASE + tag, owner, name, desc);
		Item result = get(key4);
		if (result == null) {
			if (tag <= Opcodes.H_PUTSTATIC) {
				put112(HANDLE, tag, newField(owner, name, desc));
			} else {
				put112(HANDLE, tag, newMethod(owner, name, desc, tag == Opcodes.H_INVOKEINTERFACE));
			}
			result = new Item(index++, key4);
			put(result);
		}
		return result;
	}

	/**
	 * Adds a handle to the constant pool of the class being build. Does nothing if
	 * the constant pool already contains a similar item. <i>This method is intended
	 * for {@link Attribute} sub classes, and is normally not needed by class
	 * generators or adapters.</i>
	 * 
	 * @param tag   the kind of this handle. Must be {@link Opcodes#H_GETFIELD},
	 *              {@link Opcodes#H_GETSTATIC}, {@link Opcodes#H_PUTFIELD},
	 *              {@link Opcodes#H_PUTSTATIC}, {@link Opcodes#H_INVOKEVIRTUAL},
	 *              {@link Opcodes#H_INVOKESTATIC}, {@link Opcodes#H_INVOKESPECIAL},
	 *              {@link Opcodes#H_NEWINVOKESPECIAL} or
	 *              {@link Opcodes#H_INVOKEINTERFACE}.
	 * @param owner the internal name of the field or method owner class.
	 * @param name  the name of the field or method.
	 * @param desc  the descriptor of the field or method.
	 * @return the index of a new or already existing method type reference item.
	 */
	public int newHandle(final int tag, final String owner, final String name, final String desc) {
		return newHandleItem(tag, owner, name, desc).index;
	}

	/**
	 * Adds an invokedynamic reference to the constant pool of the class being
	 * build. Does nothing if the constant pool already contains a similar item.
	 * <i>This method is intended for {@link Attribute} sub classes, and is normally
	 * not needed by class generators or adapters.</i>
	 * 
	 * @param name    name of the invoked method.
	 * @param desc    descriptor of the invoke method.
	 * @param bsm     the bootstrap method.
	 * @param bsmArgs the bootstrap method constant arguments.
	 * 
	 * @return a new or an already existing invokedynamic type reference item.
	 */
	Item newInvokeDynamicItem(final String name, final String desc, final Handle bsm, final Object... bsmArgs) {
		// cache for performance
		ByteVector bootstrapMethods = this.bootstrapMethods;
		if (bootstrapMethods == null) {
			bootstrapMethods = this.bootstrapMethods = new ByteVector();
		}

		int position = bootstrapMethods.length; // record current position

		int hashCode = bsm.hashCode();
		bootstrapMethods.putShort(newHandle(bsm.tag, bsm.owner, bsm.name, bsm.desc));

		int argsLength = bsmArgs.length;
		bootstrapMethods.putShort(argsLength);

		for (int i = 0; i < argsLength; i++) {
			Object bsmArg = bsmArgs[i];
			hashCode ^= bsmArg.hashCode();
			bootstrapMethods.putShort(newConst(bsmArg));
		}

		byte[] data = bootstrapMethods.data;
		int length = (1 + 1 + argsLength) << 1; // (bsm + argCount + arguments)
		hashCode &= 0x7FFFFFFF;
		Item result = items[hashCode % items.length];
		loop: while (result != null) {
			if (result.type != BSM || result.hashCode != hashCode) {
				result = result.next;
				continue;
			}

			// because the data encode the size of the argument
			// we don't need to test if these size are equals
			int resultPosition = result.intVal;
			for (int p = 0; p < length; p++) {
				if (data[position + p] != data[resultPosition + p]) {
					result = result.next;
					continue loop;
				}
			}
			break;
		}

		int bootstrapMethodIndex;
		if (result != null) {
			bootstrapMethodIndex = result.index;
			bootstrapMethods.length = position; // revert to old position
		} else {
			bootstrapMethodIndex = bootstrapMethodsCount++;
			result = new Item(bootstrapMethodIndex);
			result.set(position, hashCode);
			put(result);
		}

		// now, create the InvokeDynamic constant
		key3.set(name, desc, bootstrapMethodIndex);
		result = get(key3);
		if (result == null) {
			put122(INDY, bootstrapMethodIndex, newNameType(name, desc));
			result = new Item(index++, key3);
			put(result);
		}
		return result;
	}

	/**
	 * Adds an invokedynamic reference to the constant pool of the class being
	 * build. Does nothing if the constant pool already contains a similar item.
	 * <i>This method is intended for {@link Attribute} sub classes, and is normally
	 * not needed by class generators or adapters.</i>
	 * 
	 * @param name    name of the invoked method.
	 * @param desc    descriptor of the invoke method.
	 * @param bsm     the bootstrap method.
	 * @param bsmArgs the bootstrap method constant arguments.
	 * 
	 * @return the index of a new or already existing invokedynamic reference item.
	 */
	public int newInvokeDynamic(final String name, final String desc, final Handle bsm, final Object... bsmArgs) {
		return newInvokeDynamicItem(name, desc, bsm, bsmArgs).index;
	}

	/**
	 * Adds a field reference to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item.
	 * 
	 * @param owner the internal name of the field's owner class.
	 * @param name  the field's name.
	 * @param desc  the field's descriptor.
	 * @return a new or already existing field reference item.
	 */
	Item newFieldItem(final String owner, final String name, final String desc) {
		key3.set(FIELD, owner, name, desc);
		Item result = get(key3);
		if (result == null) {
			put122(FIELD, newClass(owner), newNameType(name, desc));
			result = new Item(index++, key3);
			put(result);
		}
		return result;
	}

	/**
	 * Adds a field reference to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item. <i>This method
	 * is intended for {@link Attribute} sub classes, and is normally not needed by
	 * class generators or adapters.</i>
	 * 
	 * @param owner the internal name of the field's owner class.
	 * @param name  the field's name.
	 * @param desc  the field's descriptor.
	 * @return the index of a new or already existing field reference item.
	 */
	public int newField(final String owner, final String name, final String desc) {
		return newFieldItem(owner, name, desc).index;
	}

	/**
	 * Adds a method reference to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item.
	 * 
	 * @param owner the internal name of the method's owner class.
	 * @param name  the method's name.
	 * @param desc  the method's descriptor.
	 * @param itf   <tt>true</tt> if <tt>owner</tt> is an interface.
	 * @return a new or already existing method reference item.
	 */
	Item newMethodItem(final String owner, final String name, final String desc, final boolean itf) {
		int type = itf ? IMETH : METH;
		key3.set(type, owner, name, desc);
		Item result = get(key3);
		if (result == null) {
			put122(type, newClass(owner), newNameType(name, desc));
			result = new Item(index++, key3);
			put(result);
		}
		return result;
	}

	/**
	 * Adds a method reference to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item. <i>This method
	 * is intended for {@link Attribute} sub classes, and is normally not needed by
	 * class generators or adapters.</i>
	 * 
	 * @param owner the internal name of the method's owner class.
	 * @param name  the method's name.
	 * @param desc  the method's descriptor.
	 * @param itf   <tt>true</tt> if <tt>owner</tt> is an interface.
	 * @return the index of a new or already existing method reference item.
	 */
	public int newMethod(final String owner, final String name, final String desc, final boolean itf) {
		return newMethodItem(owner, name, desc, itf).index;
	}

	/**
	 * Adds an integer to the constant pool of the class being build. Does nothing
	 * if the constant pool already contains a similar item.
	 * 
	 * @param value the int value.
	 * @return a new or already existing int item.
	 */
	Item newInteger(final int value) {
		key.set(value);
		Item result = get(key);
		if (result == null) {
			pool.putByte(INT).putInt(value);
			result = new Item(index++, key);
			put(result);
		}
		return result;
	}

	/**
	 * Adds a float to the constant pool of the class being build. Does nothing if
	 * the constant pool already contains a similar item.
	 * 
	 * @param value the float value.
	 * @return a new or already existing float item.
	 */
	Item newFloat(final float value) {
		key.set(value);
		Item result = get(key);
		if (result == null) {
			pool.putByte(FLOAT).putInt(key.intVal);
			result = new Item(index++, key);
			put(result);
		}
		return result;
	}

	/**
	 * Adds a long to the constant pool of the class being build. Does nothing if
	 * the constant pool already contains a similar item.
	 * 
	 * @param value the long value.
	 * @return a new or already existing long item.
	 */
	Item newLong(final long value) {
		key.set(value);
		Item result = get(key);
		if (result == null) {
			pool.putByte(LONG).putLong(value);
			result = new Item(index, key);
			index += 2;
			put(result);
		}
		return result;
	}

	/**
	 * Adds a double to the constant pool of the class being build. Does nothing if
	 * the constant pool already contains a similar item.
	 * 
	 * @param value the double value.
	 * @return a new or already existing double item.
	 */
	Item newDouble(final double value) {
		key.set(value);
		Item result = get(key);
		if (result == null) {
			pool.putByte(DOUBLE).putLong(key.longVal);
			result = new Item(index, key);
			index += 2;
			put(result);
		}
		return result;
	}

	/**
	 * Adds a string to the constant pool of the class being build. Does nothing if
	 * the constant pool already contains a similar item.
	 * 
	 * @param value the String value.
	 * @return a new or already existing string item.
	 */
	private Item newString(final String value) {
		key2.set(STR, value, null, null);
		Item result = get(key2);
		if (result == null) {
			pool.put12(STR, newUTF8(value));
			result = new Item(index++, key2);
			put(result);
		}
		return result;
	}

	/**
	 * Adds a name and type to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item. <i>This method
	 * is intended for {@link Attribute} sub classes, and is normally not needed by
	 * class generators or adapters.</i>
	 * 
	 * @param name a name.
	 * @param desc a type descriptor.
	 * @return the index of a new or already existing name and type item.
	 */
	public int newNameType(final String name, final String desc) {
		return newNameTypeItem(name, desc).index;
	}

	/**
	 * Adds a name and type to the constant pool of the class being build. Does
	 * nothing if the constant pool already contains a similar item.
	 * 
	 * @param name a name.
	 * @param desc a type descriptor.
	 * @return a new or already existing name and type item.
	 */
	Item newNameTypeItem(final String name, final String desc) {
		key2.set(NAME_TYPE, name, desc, null);
		Item result = get(key2);
		if (result == null) {
			put122(NAME_TYPE, newUTF8(name), newUTF8(desc));
			result = new Item(index++, key2);
			put(result);
		}
		return result;
	}

	/**
	 * Adds the given internal name to {@link #typeTable} and returns its index.
	 * Does nothing if the type table already contains this internal name.
	 * 
	 * @param type the internal name to be added to the type table.
	 * @return the index of this internal name in the type table.
	 */
	int addType(final String type) {
		key.set(TYPE_NORMAL, type, null, null);
		Item result = get(key);
		if (result == null) {
			result = addType(key);
		}
		return result.index;
	}

	/**
	 * Adds the given "uninitialized" type to {@link #typeTable} and returns its
	 * index. This method is used for UNINITIALIZED types, made of an internal name
	 * and a bytecode offset.
	 * 
	 * @param type   the internal name to be added to the type table.
	 * @param offset the bytecode offset of the NEW instruction that created this
	 *               UNINITIALIZED type value.
	 * @return the index of this internal name in the type table.
	 */
	int addUninitializedType(final String type, final int offset) {
		key.type = TYPE_UNINIT;
		key.intVal = offset;
		key.strVal1 = type;
		key.hashCode = 0x7FFFFFFF & (TYPE_UNINIT + type.hashCode() + offset);
		Item result = get(key);
		if (result == null) {
			result = addType(key);
		}
		return result.index;
	}

	/**
	 * Adds the given Item to {@link #typeTable}.
	 * 
	 * @param item the value to be added to the type table.
	 * @return the added Item, which a new Item instance with the same value as the
	 *         given Item.
	 */
	private Item addType(final Item item) {
		++typeCount;
		Item result = new Item(typeCount, key);
		put(result);
		if (typeTable == null) {
			typeTable = new Item[16];
		}
		if (typeCount == typeTable.length) {
			Item[] newTable = new Item[2 * typeTable.length];
			System.arraycopy(typeTable, 0, newTable, 0, typeTable.length);
			typeTable = newTable;
		}
		typeTable[typeCount] = result;
		return result;
	}

	/**
	 * Returns the index of the common super type of the two given types. This
	 * method calls {@link #getCommonSuperClass} and caches the result in the
	 * {@link #items} hash table to speedup future calls with the same parameters.
	 * 
	 * @param type1 index of an internal name in {@link #typeTable}.
	 * @param type2 index of an internal name in {@link #typeTable}.
	 * @return the index of the common super type of the two given types.
	 */
	int getMergedType(final int type1, final int type2) {
		key2.type = TYPE_MERGED;
		key2.longVal = type1 | (((long) type2) << 32);
		key2.hashCode = 0x7FFFFFFF & (TYPE_MERGED + type1 + type2);
		Item result = get(key2);
		if (result == null) {
			String t = typeTable[type1].strVal1;
			String u = typeTable[type2].strVal1;
			key2.intVal = addType(getCommonSuperClass(t, u));
			result = new Item((short) 0, key2);
			put(result);
		}
		return result.intVal;
	}

	/**
	 * Returns the common super type of the two given types. The default
	 * implementation of this method <i>loads<i> the two given classes and uses the
	 * java.lang.Class methods to find the common super class. It can be overridden
	 * to compute this common super type in other ways, in particular without
	 * actually loading any class, or to take into account the class that is
	 * currently being generated by this ClassWriter, which can of course not be
	 * loaded since it is under construction.
	 * 
	 * @param type1 the internal name of a class.
	 * @param type2 the internal name of another class.
	 * @return the internal name of the common super class of the two given classes.
	 */
	protected String getCommonSuperClass(final String type1, final String type2) {
		Class<?> c, d;
		ClassLoader classLoader = getClass().getClassLoader();
		try {
			c = Class.forName(type1.replace('/', '.'), false, classLoader);
			d = Class.forName(type2.replace('/', '.'), false, classLoader);
		} catch (Exception e) {
			throw new RuntimeException(e.toString());
		}
		if (c.isAssignableFrom(d)) {
			return type1;
		}
		if (d.isAssignableFrom(c)) {
			return type2;
		}
		if (c.isInterface() || d.isInterface()) {
			return "java/lang/Object";
		} else {
			do {
				c = c.getSuperclass();
			} while (!c.isAssignableFrom(d));
			return c.getName().replace('.', '/');
		}
	}

	/**
	 * Returns the constant pool's hash table item which is equal to the given item.
	 * 
	 * @param key a constant pool item.
	 * @return the constant pool's hash table item which is equal to the given item,
	 *         or <tt>null</tt> if there is no such item.
	 */
	private Item get(final Item key) {
		Item i = items[key.hashCode % items.length];
		while (i != null && (i.type != key.type || !key.isEqualTo(i))) {
			i = i.next;
		}
		return i;
	}

	/**
	 * Puts the given item in the constant pool's hash table. The hash table
	 * <i>must</i> not already contains this item.
	 * 
	 * @param i the item to be added to the constant pool's hash table.
	 */
	private void put(final Item i) {
		if (index + typeCount > threshold) {
			int ll = items.length;
			int nl = ll * 2 + 1;
			Item[] newItems = new Item[nl];
			for (int l = ll - 1; l >= 0; --l) {
				Item j = items[l];
				while (j != null) {
					int index = j.hashCode % newItems.length;
					Item k = j.next;
					j.next = newItems[index];
					newItems[index] = j;
					j = k;
				}
			}
			items = newItems;
			threshold = (int) (nl * 0.75);
		}
		int index = i.hashCode % items.length;
		i.next = items[index];
		items[index] = i;
	}

	/**
	 * Puts one byte and two shorts into the constant pool.
	 * 
	 * @param b  a byte.
	 * @param s1 a short.
	 * @param s2 another short.
	 */
	private void put122(final int b, final int s1, final int s2) {
		pool.put12(b, s1).putShort(s2);
	}

	/**
	 * Puts two bytes and one short into the constant pool.
	 * 
	 * @param b1 a byte.
	 * @param b2 another byte.
	 * @param s  a short.
	 */
	private void put112(final int b1, final int b2, final int s) {
		pool.put11(b1, b2).putShort(s);
	}
}